1. Field of the Invention
The present invention relates generally to window coverings that include horizontally or vertically disposed slats. It relates particularly to a slat made from a multi-component starting felt batt and to various uses of the slat, as is, or as a base for a fabric covering.
2. Description of the Prior Art
Window coverings (e.g., blinds having vertically or horizontally disposed slats) generally employ slats fabricated of rigid materials such as metal, plastic, or wood. While these materials may each provide certain advantages, they all have hard surfaces and reflect, rather than absorb, sound. They are also hard to the touch, and do not have an aesthetically pleasing finish when compared to the xe2x80x9csoftxe2x80x9d fabric window coverings, such as pleated, cellular or Roman shade products. Moreover, rigid slats cannot generally be repaired if deformed to the point that they crease, crack or break. Such damage may occur when, for example, a person manually spreads apart the slats to look through a blind.
It is known to provide vertical blinds having slats comprised of strips of textile material, some of which comprise a backing and a facing. The edges of the facing may be rearwardly inturned, and the edges of the backing may be forwardly inturned, so that the backing and the facing may be secured to each other. See U.S. Pat. No. 4,519,435, issued May 28, 1985 to Stier and entitled xe2x80x9cSlats For Venetian Blindsxe2x80x9d. It is also known to provide vertical blinds covered with fabric suitable for making clothing or drapes, the fabric being attached to a backing member by either sewing or a heat bonding process. See U.S. Pat. No. 5,061,132 issued Feb. 11, 1997 to Goodman for xe2x80x9cVertical Blinds And Method For Making The Samexe2x80x9d. It is further known to produce slats from linear, synthetic polyester fibers, which serve as protection against light, and which have been stiffened permanently by plastification. See U.S. Pat. No. 4,309,472 issued Jan. 5, 1982 to Gotting, et al. for xe2x80x9cSlats Serving As Protection Against Lightxe2x80x9d. It is also known to make blind fabric utilizing natural or synthetic fibers of fabric as base materials to form an inexpensive fabric used in conjunction with conventional venetian and vertical blinds and formed by a method comprising dipping, compressing, tentering, slitting into desired widths, heating, and forming. See U.S. Pat. No. 5,273,781 issued Dec. 28, 1993 to Shu for xe2x80x9cMethod Of Making Blind Fabricsxe2x80x9d. Another know slat adds a tape or sheet of sound deadening material to a conventional slat. See U.S. Pat. No. 3,472,305 issued Oct. 14, 1969 to Lefes for xe2x80x9cSoundproof And Heatproof Slat For Venetian Blindsxe2x80x9d. All such slat configurations preceding the present invention have one or more disadvantages, generally relating to manufacturing cost, lack of ability to absorb sound, and/or the absence of a soft fabric look and feel.
Other slats which include components other than a single piece of slat material, are described in U.S. Pat. No. 2,121,217 issued Jun. 21, 1938 to Ellis for xe2x80x9cVenetian Blind Slatxe2x80x9d; U.S. Pat. No. 2,123,010 issued Jul. 5, 1938 to Kahn for xe2x80x9cVenetian Blindxe2x80x9d; U.S. Pat. No. 2,590,204 issued Mar. 25, 1952 to Phillips for xe2x80x9cAcoustical Venetian Blindxe2x80x9d; U.S. Pat. No. 5,101,876 issued Apr. 7, 1992 to Zak for xe2x80x9cLouver Covering Systemxe2x80x9d; and U.S. Pat. No. 5,141,042 issued Aug. 25, 1992 to Schwaegerle for xe2x80x9cWeb Covered Vertical Blind Slat Assembliesxe2x80x9d.
The art of producing non-woven felts is also well-developed. For example, it is known that non-woven fabrics may be xe2x80x9cneedledxe2x80x9d to substrates or to other layers of non-woven fabric to attach the two together. See, for example U.S. Pat. No. 4,154,889 issued May 15, 1979 to Platt for xe2x80x9cNon-Woven Fabric, Method And Apparatus For Its Manufacturexe2x80x9d and U.S. Pat. No. 4,490,425 issued Dec. 25, 1984 to Knoke, et al. for xe2x80x9cFused And Needled Non-Woven Interlining Fabricxe2x80x9d. A three layer laminate which includes a layer of meltblown fibers between two layers of needle punched fibers, the three layers being ultrasonically welded together, is shown in U.S. Pat. No. 5,466,516 issued Nov. 14, 1995 to Lutzow, et al. for xe2x80x9cThermoplastic Fiber Laminatexe2x80x9d. Furthermore, the use of felts comprising at least two different thermoplastic polymers having different melting points is known, as illustrated in U.S. Pat. No. 5,593,768 issued Jan. 14, 1997 to Gessner for xe2x80x9cNon-Woven Fabrics And Fabric Laminates From Multi Constituent Fibersxe2x80x9d.
It would be advantageous to provide a window covering slat which is economical to manufacture, provides the pleasant appearance of a soft-textured fabric, and which absorbs sound. It would also be advantageous to provide a window covering slat which does not dent or readily crease and which is easily repaired should it nonetheless become damaged in this way.
A feature of the present invention is to provide a window covering which includes a plurality of slats, each slat including a layer formed from a felt batt, and which may, in some embodiments, include a second layer of fabric secured to a slat base.
Another feature of the present invention is to provide a slat for a window covering which includes a plurality of slats, each slat including a slat base thermally formed to a predetermined shape from a felt batt.
Yet another feature of the invention is a method of fabricating a slat for a window covering, the method including the steps of thermally forming a slat base from a felt batt, and optionally securing a layer of fabric to the slat base.
A different feature of the present invention is to provide a slat for window coverings, including horizontal and vertical blinds, which may be made in a variety of cross-sectional shapes, including rectangular, S-shaped, curled, and the like.
A still further feature of the present invention is to provide a slat for window coverings which displays a different appearance on one side than on the other, e.g. a decorative appearance on one side and a functional appearance on the other side.
A still further feature of the present invention is to provide a slat for window coverings in which a fabric applied to a slat base may be selected from woven, non-woven, synthetic or natural fabrics.
How the foregoing and other features of the present invention are accomplished, individually or in combination, will be described in the following detailed description of certain preferred embodiments, taken in conjunction with the drawings. Generally, however, the features are accomplished by forming a slat base into a desired shape from a felt batt and optionally applying a fabric layer thereover. The fabric may be woven, non-woven, synthetic or natural and, when used, is selected primarily for its aesthetic properties. The felt batt is preferably composed of at least two types of thermoplastic fibers having different melting points and is thermally treated at a temperature above the melting point of the fiber having the lower melting point to form a polymer matrix which at least partially envelopes the higher melting point fibers. The felt batt is compressed when heated and formed into its desired shape. A fabric may be attached to the slat before or after such thermal treatment, and the thermal treatment step can be carried out in a mold to simultaneously form the slat into its desired form. Alternatively, the slat, after an initial thermal treatment, can be placed into a mold and be re-heated to form the desired final shape. Other ways in which the above-referenced and other features of the present invention are accomplished individually or in various combinations will become apparent to those skilled in the art after they have read this specification, and such other ways are deemed to fall within the scope of the present invention if they fall within the scope of the claims which follow.